U.S. patent number 5,474,226 [Application Number 08/255,274] was granted by the patent office on 1995-12-12 for projectile welding.
This patent grant is currently assigned to Orbit Technologies, Inc.. Invention is credited to Adrian A. Joseph.
United States Patent |
5,474,226 |
Joseph |
December 12, 1995 |
Projectile welding
Abstract
Disclosed in this description is a means for welding materials
together by shooting a projectile partially therethrough.
Inventors: |
Joseph; Adrian A. (Los Angeles,
CA) |
Assignee: |
Orbit Technologies, Inc.
(Carlsbad, CA)
|
Family
ID: |
22967599 |
Appl.
No.: |
08/255,274 |
Filed: |
June 8, 1994 |
Current U.S.
Class: |
228/112.1;
228/115; 228/139 |
Current CPC
Class: |
B23K
20/08 (20130101) |
Current International
Class: |
B23K
20/08 (20060101); B23K 20/06 (20060101); B23K
020/06 () |
Field of
Search: |
;228/139,112.1,107,115 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Ramsey; Kenneth J.
Attorney, Agent or Firm: Ladas & Parry
Claims
I claim:
1. A method for welding material together comprised of shooting a
projectile partially through the material at a velocity such that
said projectile and said material form a weld.
2. The method of claim 1 wherein said projectile is of the same
material as said material.
3. The method of claim 1 wherein said projectile is shot
perpendicular to said material.
4. A device for welding material by shooting a projectile partially
through said material, said device being comprised of:
impact means;
stopping means, wherein said projectile is impacted by said impact
means and thereby shot partially through said material to abut
against said stopping means.
5. The device of claim 4 wherein said stopping means is mobile
enough to absorb the impact of said projectile.
6. The device of claim 5 further comprising holding means for
holding the material to be welded against said stopping means.
7. The device of claim 4 wherein said stopping means has a surface
shape which causes said projectile to flatten thereagainst thus
forming a flattened end on one side of said welding material, said
impacter having a shape causing the opposing side of said
projectile to form a flattened end on a side opposing said one side
of said welding material, such that the weld formed by said
projectile and said material is flattened at opposing ends and
against said material.
8. The device of claim 4 wherein there is a plurality of impact
means, stopping means, and projectiles such that a plurality of
welds may be formed at one time.
9. A device for welding material by shooting a projectile partially
through said material, said device being comprised of:
impact means; and
stopping means, wherein said projectile is impacted by said impact
means and thereby shot partially through said material to abut
against said stopping means, and wherein said projectile has a
rounded or pointed tip extending from (atop) a generally
cylindrical body, said tip being located opposite said impact means
such that when said projectile is shot by said impact means said
tip will abut against said stopping means.
10. The projectile of claim 9 wherein said body has an indentation
around its diameter.
11. An article of manufacture having weld formed between metals,
said weld being comprised of a projectile that is flattened at both
ends against said metals to assist in holding said metals
together.
12. The article of claim 11 wherein said metals and said projectile
are comprised of the same material.
Description
FIELD OF THE INVENTION
The present invention relates to a mechanism and a method for
joining metals together.
BACKGROUND OF THE INVENTION
There is much disclosed and written about the joining of materials
together and particularly metals through various welding
techniques. Some techniques make use of chemical means, others look
to the use of heat and still others involve ultrasonic devices.
Some examples of such devices and methodology are found in U.S.
Pat. Nos., 4,037,078; 4,368,371; 4,591,687; and 5,082,160. The
present invention and method is quite different. Joinder is
accomplished by shooting a projectile partially through the metals
to be joined.
Looking to the joining or welding of aluminum or its alloys, there
is the issue of the formation of "hot tears". The "hot tear" effect
manifests itself in the form of a crack generated behind the solid
front of a weld.
To understand this situation, one must look to the make-up of the
metal. The crystallograins of weld metal will assume the
orientation of the parent seed crystal adjacent to the fusion zone
even though competitive growth between grains will exist owing to
the relationship between preferred growth directions and the
thermal gradients in the weld pool. The nucleation of new grains
with more favorable orientations is seldom observed in the absence
of heterogenous nuclei.
Prior art improvements have been achieved in the weldability of
metals and in particular aluminum and its alloys. This has been
accomplished largely by refinement of the weld metal grain size by
adding an element which will provide some type of substrate upon
which new grains of weld metal can form. Unfortunately, the prior
art is anything but conclusive as to the relationship between
usable intermetallic inclusions in the welding consumable, such as
the welding wire, and the process of manufacturing the consumable.
Similarly, the prior art is silent on the sensitivity of the
intermetallic inclusions in the consumable to the thermodynamics of
the weld itself.
It is believed that the present invention addresses these issues by
presenting a process which may be used with or without electrical
power. More precisely, the present invention operates without the
application of heat to the projectile or the material to be
welded.
SUMMARY OF THE INVENTION
Disclosed herein is a method for welding or joining materials
together by shooting a projectile partially therethrough. It is
further disclosed that the projectile is made of the same material
as the material to be joined. Also disclosed is a device for
projecting said projectile at a high impact velocity into and at
least partially through the material to be joined. Further
disclosed is a stopping mechanism on said device for impacting
against the projectile.
It is believed that this method of joinder achieves a multi
molecular nucleation between the materials to be joined. The
projectile will penetrate at high speed the layers of material and
crush against the stopping mechanism. The high speed of penetration
of the projectile through the material will cause a local micronic
melting of the material around the projectile and of the projectile
itself since the two are of the same material.
Due to the fact that the thermo-velocity relation is only at a
micro level, cracks do not seem to occur and a strong reliable
substructure bonding takes place. The method and device are
particularly effective for aluminum and its alloys. Its practice
and usage are fast and economical as compared to conventional
welding techniques.
DRAWINGS
FIG. 1 is diagrammatic view of one embodiment of a device of this
invention.
FIGS. 2 through 5 are diagrammatic views of projectiles of this
invention.
FIG. 6 is a diagrammatic view of two pieces joined by a
projectile.
DETAILED DESCRIPTION
In FIG. 1 two pieces of material to be joined such as aluminum or
aluminum alloy (1) are held in a vice-like device which is the
joining mechanism (100) herein. On one side of joining mechanism
(100) is an impacter (2) and at the opposing side of joining
mechanism (100) at the same level as impacter (2) is stopping
mechanism (8). Extending parallel to impacter (2) and the pieces
(1) being held by joining mechanism (100) is a projectile container
(7) which joins u-shaped arm (9) that extends below pieces (1).
U-shaped arm (9) connects at an end opposite its connection to
projectile container (7), to stopping mechanism (8). As can be seen
from FIG. 1, one side of projectile container (7) connects to
impacter (2). The opposing side of projectile container (1)
connects to a barrel (5) which acts in part to hold pieces (1)
against stopping mechanism (8).
Impacter (2) is comprised of a hammer (3) movably situated with
respect to a locking mechanism (4) and spring means (10). This is a
very rough depiction of an impacter device and any impacter device
is suitable. The device must merely cause a hammer (3) to move
forcefully against a projectile held in projectile container (7) to
propel that projectile into barrel (5) and into pieces (1).
Impacters of this nature are: electro-magnetic, gas cylinder,
hydraulic, mechanical such as mechanical off-center drive-shaft
with a clutch, and explosive-triggering devices. The locking
mechanism (4) may well act as a clutch unit to compress a
mechanical lever that would lock hammer (3) after each impact.
Projectile container (7) preferably includes a loading mechanism
such as a magazine so that more than one projectile can be housed
therein. On the other hand, the projectiles could simply drop from
a holder into the container (7) or a chain driven loader held
within container (7) is possible for holding projectiles and
delivering them to a position for impact by the hammer (3).
It is preferred that hammer (3) and barrel (5) be in alignment with
each other and with the longitudinal axis of the projectile. It is
also preferred that the barrel (5) be situated perpendicularly to
the pieces (1) or at least be located in some means such that the
projectile is delivered perpendicularly against pieces (1).
Some sample projectiles are seen in FIGS. 2 through 5. They are
shown with cylindrical bodies (20) and tips (22) and are longer
than they are wide thereby having a clear longitudinal axis along
such length. In FIGS. 2 through 5, the tips (22) are symmetrically
formed and generally rounded or pointed. It is intended that the
tipb 54742366.001 impact first the pieces (1) to be joined. In the
FIGS. 4 and 5, bodies (22) exhibit a concave groove or dent (24)
therearound. As noted earlier herein, the projectiles are generally
preferred to be made of the same material as the materials to be
joined, or pieces (1). The configuration shown in the last two
figures wherein grooves (24) are shown would likely be used when
higher than usual friction is expected at impact causing excess
material to melt upon contact of tip (22) of the with pieces
(1).
The impact strength, size of projectile, and length of barrel (5)
are all dependent upon the material pieces (1) to be joined and, of
course, the projectile material. This may be readily calculated
when it is understood that the projectile is to penetrate pieces
(1) to be joined and the mutual at least surface molten state of
projectile and pieces (1) in the area surrounding the projectile is
desired.
The device of FIG. 1 has adjustment means not shown for moving
stopping mechanism (8) toward and away from barrel (5) to adjust to
the width of pieces (1) to be held. It is also possible that barrel
(5) could be adjustable in length or detachable to place different
lengths of barrels (5) therein. Additionally, the inventor
contemplates the use of a plurality of barrels (5) and impactors in
one mechanism or even a mechanism to rotate pieces (1) between
barrel (5) and stopping mechanism (8) so that a plurality of points
of joinder are available.
U-shaped arm (9) is somewhat flexible to absorb the shock of the
impact of the projectile against the face of stopping mechanism
(8). Preferably, the face of stopping mechanism (8) which is
impacted by tip (22) is of tool steel and preferably but not
necessarily, the face of stopping mechanism (8) is flat. Using
aluminum or aluminum alloy as pieces (1) and projectiles of like
material, the surface hardening of the face of tool steel of 58-62
Rc was sufficient. It is understood that the face of the stopping
mechanism (8) must be constructed to arrest the motion of the
projectile as it begins to penetrate completely through pieces
(1).
In the use of aluminum or aluminum alloy as pieces (1) and the
projectiles, hammer (3) used was made from stainless steel 316 or
Tool Steel. Needless to say, the portion of the hammer (3) which
abuts the end of the projectile to project it into barrel (5) is of
a size that is proportional to the size of the projectile to
facilitate obtaining the desired speed of the projectile as it
enters the barrel (5). In these tests, the barrel (5) was made of
stainless steel 316 or high tempered steel.
FIG. 6 shows pieces (1) joined by a projectile. The flattened tip
(22) and opposing body (20) end results from the impact of the
projectile with pieces (1) and in the case of tip (22) its abutment
against stopping mechanism (8)
CONCLUSION
Some of the salient points set forth above are as follows.
Disclosed is a method and device for joining or welding materials
such as aluminum or aluminum alloy. The method involves shooting a
projectile of the same material as that material to be joined at
the material to be joined and shooting it preferably perpendicular
to that material. The speed at which the projectile is shot taking
into account its own mass will cause the projectile to impact and
penetrate the pieces of material to be joined. In doing so, the
friction between the projectile and the material to be joined will
result in micro melting of the material surrounding the projectile
as well as the projectile and thereby the welding of the two base
materials. The weld created in this fashion will not exhibit
perceivable crating or cracking in the substructure of the joint
point.
To propel the projectile, an impacter is used. The impacter may be
of any known construction such as explosive, mechanical, hydraulic,
gas-driven, or electro-magnetic.
The projectile is to be released in place for impact by the
impacter such that interlayer stresses in the projectile are
minimized. The projectile is preferably of the same material as the
materials to be joined or welded.
To obviate manual loading, a loading mechanism is suggested for use
with the impacter. Such mechanism may include a magazine such as
used in firearms. Passage of the projectile through the pieces to
be joined is stopped by a stopping mechanism which may be a single
or multiple unit. It is only necessary that the tip of the
projectile and its opposite end are ultimately flattened after
impact and joining the pieces to be joined. These flattened ends
create additional joining forces to hold the pieces that are joined
together.
The present invention is claimed as follows.
* * * * *